Thursday, September 22, 2005

The Terminal Velocity of Cats

Falling Cats in the city, an unavoidable cost of pet ownership, and it's inyteresting that there is a Terminal Velocity for Cats,

Cats have evolved with a innate instinct to land on their feet, a trait that suggests that cats are susceptible to falling in nature. Cats are especially vulnerable to falling when they are stalking prey and they lock-in on their target and I’ve seen several cats meet an untimely end by darting into traffic in pursuit of a bunny.

Cats also love to be outside, which is a special problem for cat owners in the city with balconies, verandas or penthouses. Just a momentary lapse in security and you might witness kitty do a half-Nelson off of your 40th floor veranda, in pursuit of a pigeon.

Falling cats happen and I saw a fascinating article recently about the terminal velocity of falling cats, whose terminal velocity is 60 MPH.

"Cats have a nonfatal terminal velocity (sounds like a contradiction in terms, but most small animals have this advantage). Once they orient themselves, they spread out like a parachute. There are cats on record that have fallen 20 stories or more without ill effects.

As long as the cat doesn't land on something pointy, it's likely to walk away."

It appears that this was a legitimate real-world study by the American Veterinary Association, scientific research where you observe the real-world and develop a heueristic model:

"But the believers trot out a 1987 study from the Journal of the American Veterinary Medical Association. Two vets examined 132 cases of cats that had fallen out of high-rise windows and were brought to the Animal Medical Center, a New York veterinary hospital, for treatment. On average the cats fell 5.5 stories, yet 90 percent survived."

The seven story threshold and terminal velocity

Could it be true that in falls above seven stories that cats become aerodynamic? There is some compelling evidence for this:

"When the vets analyzed the data they found that, as one would expect, the number of broken bones and other injuries increased with the number of stories the cat had fallen--up to seven stories.

Above seven stories, however, the number of injuries per cat sharply declined. In other words, the farther the cat fell, the better its chances of escaping serious injury.

The authors explained this seemingly miraculous result by saying that after falling five stories or so the cats reached a terminal velocity--that is, maximum downward speed--of 60 miles per hour. Thereafter, they hypothesized, the cats relaxed and spread themselves out like flying squirrels, minimizing injuries."

The “dumpster” skew?

Of course, we must always consider those clearly deceased cats who were never brought in for medical attention:

"The potential flaw is this: the study was based only on cats that were brought into the hospital. Clearly dead cats, your basic fell-20-stories-and-looks-like-it-came-out-of-a-can-of-Spam cats, go to the Dumpster, not the emergency room. This may skew the statistics and make falls from great distances look safer than they are."

However some researchers believe that the “flying cat” effect is real and that there is no dumpster skew:

"Dr. Garvey was adamant that the omission of nonreported fatalities didn't skew the statistics. He pointed out that cats that had fallen from great heights typically had injuries suggesting they'd landed on their chests, which supports the "flying squirrel" hypothesis."

Who’s right, well there is not enough data yet. However, it does appear that dead cats are now being considered in Germany as an alternative fuel source.